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First view of Mars


DomDubois

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Got my first view of Mars tonight. It's barely over the tree line and honestly I think I still had some branches in there :p . Popped in my 9mm and so far no real detail but I will try again in an hour once its gotten a bit darker. Im using my 10" dob, so im getting quite a bit of coma. How much of that is weather related vs me needing a coma corrector? Haha. I've read that the faster scopes usually benefit from having one, I'm interested in what you guys think.

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A fast newtonian will benifit from a coma corrector for visual. Not sure if you have one in mind but I read reasonable things about the Astro-Tech offering and the cost was fair.

Another thing I have also read it that for visual Mars will benefit from the use of an IR filter.

Mars is small, so never Jupiter like in what you will see, and the last time Mars was well placed some people managed good views others were frustrated. Ratio of 1 happy to 3 or 4 frustrated.

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Coma should not be an issue in the central area of the field of view. When objects are relatively low down you often see atmospheric distortion due to viewing the object through somewhat more atmosphere. This can cause what looks like false colour around the top and bottom limb of an object like Mars, Jupiter, the Moon etc.

If you are viewing an object either thorough or even near to obstructions like twigs, branches, rooflines, phone lines etc, etc you can see additional diffraction affects as well. It's best to let your intended target rise as far above the horizon and such obstacles as possible for the best views.

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I've never seen Mars in all the years I have had my telescope but plan on seeing it tonight, it is low in the sky and reaches roughly the same position in the sky as Sirius I think which puts it just above some houses, so I expect the view to be god awful with the heat from the houses, street lights etc but as long as I can see a small red disk I will happy :)

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How about masking off the front of your tube, but leave apertures for the incoming light in the four places between the inner tube wall,

and the edge of the Secondary, thereby eliminating most of the obstruction that can  degrade fine detail. Worth a try.

Don't worry about losing aperture, During a close Mars opposition in 2003, closest in 60,000 years, I was at a star party and one guy was viewing the planet with a f8  4.5 reflector with various filters.

It was astonishing how much detail was visible in that little instrument. The planet was around 35,000,000 miles from earth at that time, so it was an appreciably large disc, but nevertheless,

I was impressed. A larger objective will give better resolution, but it will also collect more of the bad stuff in the atmosphere, and pretty much negate the advantages light buckets can provide.

Smaller instruments are quite capable of delivering planetary detail, given clear and steady seeing, which often arrives for fleeting moments only in the UK, but it can be memorable when you are at the eyepiece at that moment.

The drawback this time around is the low declination of the planet, so a good Southern aspect is required.

Ron.

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Seen it once or twice. Got to be honest I was a bit disappointed, I was expecting a bit more. Not quite sure what though

Did make out the red glow, may need a bit more time with it.

Probably expecting too much with looking at Jupiter most of the winter

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[QOUTE] How about masking off the front of your tube, but leave apertures for the incoming light in the four places between the inner tube wall,

and the edge of the Secondary, thereby eliminating most of the obstruction that can degrade fine detail. Worth a try.

This really won't work... You are just making enormously thick spider vanes. Far from removing the obstruction, you will have made it many times larger.

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